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		Access Method Operations
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            <h2 class="title" style="clear: both"><a id="am_close"></a>Database close</h2>
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      <p>The <a href="../api_reference/C/dbclose.html" class="olink">DB-&gt;close()</a> database handle closes the <a href="../api_reference/C/db.html" class="olink">DB</a> handle.  By
default, <a href="../api_reference/C/dbclose.html" class="olink">DB-&gt;close()</a> also flushes all modified records from the
database cache to disk.</p>
      <p>There is one flag that you can set to customize <a href="../api_reference/C/dbclose.html" class="olink">DB-&gt;close()</a>:</p>
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              <a href="../api_reference/C/dbclose.html#dbclose_DB_NOSYNC" class="olink">DB_NOSYNC</a>
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          <dd>Do not flush cached information to disk.</dd>
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        <strong>It is important to understand that flushing cached information
to disk only minimizes the window of opportunity for corrupted data, it
does not eliminate the possibility.</strong>
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      <p>While unlikely, it is possible for database corruption to happen if a
system or application crash occurs while writing data to the database. To
ensure that database corruption never occurs, applications must either:</p>
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          <li>Use transactions and logging with automatic recovery.</li>
          <li>Use logging and application-specific recovery.</li>
          <li>Edit a copy of the database, and, once all applications
using the database have successfully called <a href="../api_reference/C/dbclose.html" class="olink">DB-&gt;close()</a>, use
system operations (for example, the POSIX rename system call) to
atomically replace the original database with the updated copy.</li>
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